\frametitle{Continuity: Examples}
    A function $f$ is \emph{continuous form the right} at a number $a$ if
      \lim_{x\to a^+} f(x) = f(a)
    A function $f$ is \emph{continuous form the left} at a number $a$ if
      \lim_{x\to a^-} f(x) = f(a)
    Where is $\lfloor x \rfloor$ (dis)continuous?
      \lfloor x \rfloor = \text{`\;the largest integer $\le x$\;'}
      \item<4-> discontinuous at all integers
      \item<5-> left-discontinuous at all integers\\
        $\lim_{x\to n^-} \lfloor x \rfloor = n-1 \ne n = f(n)$
      \item<6-> \alert{but} right-continuous everywhere\\
        $\lim_{x\to n^+} \lfloor x \rfloor = n = f(n)$
      \foreach \x in {0,1,2,3} {
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